Thor's nuclear-powered hammer

Thor, the Marvel Comics superhero, hammered his way into movie theaters over the weekend, saving the world, winning Natalie Portman and grossing about $66 million. Kenneth Branagh's "Thor" is based on Stan Lee's Thor, which is based on the Thor of Norse mythology — god of thunder and protector of mankind.

Some pioneering scientists of the early 19th century were so taken with Thor's immortal powers that they named a radioactive element after him. Nearly two centuries later, some modern scientists, including a Nobel Prize laureate, believe thorium could play a major role in saving mankind from global warming.

The silvery metal could be — by some estimates, it already is — the next big leap in reactors, the fuel that could give the stalled nuclear renaissance a post-Fukushima boost. It is said to be far safer, far more abundant and less expensive than uranium, leaving less waste and, in some estimations, reducing the risk of explosions and meltdowns at power plants to zero.

Patrick Cox, a technology watcher and self-described "transformational profit seeker" for the Baltimore-based economic prognosticator Agora Financial, remains bullish on a nuclear renaissance despite Fukushima, and his reason is about the size of a golf ball.

"Imagine," he says, "a piece of rock the size of a golf ball giving a person a lifetime supply of electricity. A piece the size of an SUV could give a lifetime supply of energy to a town of about 50,000 people."

Nobel physicist Carlo Rubbia's widely quoted estimate is that a ton of thorium can produce as much energy as 200 tons of uranium, or 3.5 million tons of coal.

If there is ever going to be a nuclear expansion sufficient to significantly reduce coal-fired (and greenhouse gas-producing) electrical generation, thorium may be the answer, say its supporters. It can solve a lot of the problems associated with the present generation of nuclear reactors and instill public confidence in atomic energy as the long-term alternative to fossil fuels.

China considers thorium technology environmentally safe, cost effective and politically palatable; it is pushing ahead with its development. So are India and Russia. The pro-nuclear French are not in the game yet because they have invested heavily in the present generation of reactors. The U.S. used thorium to breed nuclear fuel nearly 50 years ago but moved heavily into uranium in order to have the weapons-grade plutonium needed in the Cold War. Thorium provides no such byproduct.

Mr. Cox and other thorium enthusiasts say theirs is a superior fuel that addresses all of the problems associated with uranium. Kirk Sorensen, a former NASA engineer and a thorium expert, told the London Telegraph recently that thorium reactors are inherently less prone to problems — if they overheat, they shut down. "They operate at atmospheric pressure, so you don't have the sort of hydrogen explosions we've seen in Japan," Mr. Sorenson said. "One of these reactors would have come through the tsunami just fine. There would have been no radiation release."

He added, "Once you start looking more closely [at thorium], it blows your mind away. You can run civilization on thorium for hundreds of thousands of years, and it's essentially free."

Thor's namesake is believed to be the 39th most common element on the planet. India and Australia have tons of it. "Norway has so much [thorium] that Oslo is planning a post-oil era where thorium might drive the country's next great phase of wealth," reports Ambrose Evans-Pritchard, international business editor of the Telegraph.

There is plenty of thorium in the United States but no plan yet to move it into development here. Even then, it could take 20 years to get thorium-based reactors online, according to Bjorn Frogner, a trained nuclear engineer who serves as entrepreneur in residence at the University of Maryland, Baltimore County's clean energy incubator program. "Keep in mind," he said, "that building and licensing a new proven standard nuclear power plant takes at least eight years. The thorium plants need to go through extensive demonstration, licensing and analysis before anybody can make a decision to build them commercially."

Mr. Cox says a Virginia company, Lightbridge Corp., is developing thorium fuels to replace uranium. "It's analogous to switching your car from leaded to unleaded gasoline, as no modifications to the power plant are needed," the Lightbridge CEO, Seth Grae, told Mr. Cox. "We could deploy the fuel as soon as the development program is completed and the nuclear regulatory approval process is finished."

Memo to President Barack Obama for your next meeting with the energy secretary, another Nobel winner: Ask about thorium — and what are we waiting for?